Snowy owls are moving through Wisconsin from northern Canada, and the state Department of Natural Resources and Wisconsin eBird say the birds are staging a possibly historic movement from the Great Lakes to the Atlantic Coast.

As of Sunday, there were 55 reports of the birds in Wisconsin. That compares with about 115 at the same time in 2011-'12, but it's ahead of the pace of last year at this time, when 30 to 35 snowy owls had been observed.

Snowy owls have been seen along the Lake Michigan corridor, including the Milwaukee area.

"We're seeing a significant number of snowy owls this fall and early winter — well above average," Brady said in a DNR update on the birds' movements.

"So far, the flight is not as big here as two years ago, but we are on the western edge of a massive and possibly historic irruption from the Great Lakes east to the Atlantic Coast, an event that's making national headlines," he said.

Experts aren't sure of the reasons behind this year's movement, but there is a good chance it's tied to lemmings, the owl's favorite prey.

One theory is that a large population of lemmings in Canada allowed the owls to raise their young, and the young owls are now dispersing to find their own territory.

But another theory holds that the lemming population was low, which harmed reproduction. Now owls of all ages are flying south.

About Lee Bergquist

Lee Bergquist covers environmental issues and is author of "Second Wind: The Rise of the Ageless Athlete."